Improvement in bit-stocks



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BIEINJAIVIIN DARLING, OF BRIDGEWA'IER, MASSACHUSETTS.

I Letters Patent No. y83,261, dated October 20, v1868.

The Schedule referred to in these Letters Patent and making part of the same.

To all lwhom it may concern:

Be it known that I, BENJAMIN DA1-mme, of Bridgewater, in the county of Plymouth, and State of Massa chusetts, have invented anew and useful Improvement in Bit-Stock; and I do hereby declare that the following is va full, clear, and exact description thereof, which willv enable those skilled in the ait to make and use the same, reference being had to the accompanying drawings, forming part of this specification.

.The object of this invention is-to constructa bitstock, so that the shank of the bit or boriiiganger may be firmly held, Without the use of springs or screwnuts, and so that the bits or angers may be used withoutalteiingtheir shanks, o1' ling them in any manner.

And the invention consists in the use of sliding jaws, and in the manner in which. they are operated, as I will proceed to describe.

Figure 1 represents a longitudinal view of the stock, showing .the method of operating the sliding jaws.

Figure 2 isa section through the line x x, giving a side view of the jaws, and' 'showing the manner in which they grasp the shank of the bit.

Figure 3 is a top view o'f the jaws and compressingband. A

Similar letters of reference indicate 'corresponding parts.

A is the stock, which is made with a socket in its end for receiving the shank of the bit, as seen in g. 2.

B B represent the sliding jaws. These jaws enclose thesocket-shank of the stock,

jand, passing below it, are attached to a lever, G, at c.

D is the fulcrum of the lever, which is on a proj ectjing arm, E, of the stock A.

F represents an elongated band, which is formed on or attached to the socket-end of the stock A.

The jaws B B pass through the apertiues y g on the sides ofthe socket-end, as seen in the drawing.

Theouter sides ofthe jaws form inclined planes, h

i h,`which inclined siufaces are in contact with the outer portions of the apertures g, so that when, bythe action of the lever C, the jaws are drawn downward, the jaws are brought together or approach each other so as to -grasp the shank of the bit.

The jaws, by their shanks, are loosely attached to the lever G, and while they have suicient play in the band-apertures g to allow of' their expansion and contraction by their sliding movement, all lateral movement is prevented by the band.

The lever C is kept in place (when the bit is fastened) by the lugs i 011 the stock, there being sufficient lateral play or spring allowed to the lever for this purpose.

There may be a little exibility'allgwed to the Shanks of the jaws, which wouldV cause the" i to open andexpaud -when they are raised,'but th-.tt is not deemed essential.

The sliding' motion' of the jaws may be produced otherwise than by a lever, as, for instance, by a screw or a cam.

I do not, therefore, confine myself to theV use of a lever for that purpose, but to any device by which the sliding or longitudinal motion of the jaws may be produced.

The advantages of this arrangement are many and obvious.

Common wood-screws may be held in the jaws, with a short` screw-driver in the socket behind the screw, with the bit of the screw-driver in the nick of the screw, so that such screws maybe started and partly driven, in situations where it is inconvenient for the'operator to use both hands for the purpose of driving the screw.

The rigid fastening,-and the ease and .rapidity with which a bit is fastened 'and unfastened, the simplicity and durability of the parts, render this arrangement superior to all others for the purpose intended.

I claim as new, and desire to secure by Letters Patent- In combination with a bit-stock, the sliding jaws B B, whereby a bit or auger is fastened to the stock, substantially in the manner herein shown and described.

lhe above specification of my invention signed by me, this 6th day of June, 1868.

BENJAMIN DARLING.

Witnesses:

FRANK BLOCKLEY, ALEX. F. ROBERTS. 

